This paper describes the development of a human electrical phantom at a low-frequency band. The conventional highly hydrous electromagnetic phantom does not mimic the electrical properties of a living body. The electrical properties of the newly developed phantom, by adding a carbon microcoil (CMC) and NaCl to the conventional phantom, are in good agreement with those of a living body. In addition, the electrical properties of the phantom with a CMC and twice the amount of NaCl added are evaluated at frequency bands above 300 MHz, similar to the conventional highly hydrous gel phantom. The results show that the newly developed phantom can effectively function in the conventional target frequency band by a simple mechanism.